This invention relates generally to dynamic functional imaging of biological objects and, more particularly, to the utilization of a non-rigid object holder in conjunction therewith, and, even more specifically, for use in the screening for breast cancer.
One of the largest health problems facing the public today relates to cancer and devising safe and accurate screening procedures especially for breast cancer. There is a substantial difference between breast cancer diagnostics and breast cancer screening, in that breast cancer diagnostics are applied when a patient appears in a doctor""s office or hospital with an already existing breast problem. Breast cancer screening relates to cancer detection prior to symptoms occurring. It is hoped with a proper breast cancer screening program that the treatment of breast cancer and potential breast cancer can take place at an early stage and, therefore, effect a high cure rate.
One of the common breast cancer screening procedures in use today involves the use of X-ray radiation during mammography as well as during breast cancer diagnostics with the utilization of stereotaxic mammography which is utilized to localize the pathology, and simultaneously perform a needle biopsy in conjunction therewith to identify the malignancy. Such screening and diagnostic techniques, based on revealing of morphological changes in the breast, many times comes about too late for appropriate treatment, is expensive to perform and in many instances is harmful to the patient by exposing them to X-ray radiation. Furthermore, since the diagnosis obtained through mammography results in a high rate of false positive diagnoses, approximately five times as many patients are exposed to unnecessary X-ray radiation than necessary.
An additional problem for the mammography application to breast cancer screening is the strong compression (up to 30 psi) of the breast between two rigid plates (holder) to immobilize the breast during examination to decrease x-ray scattering in breast tissue. This compression creates substantial discomfort as well as pain for the patient and may even be harmful since there is a danger of cancerous cells disseminating if a lesion is disrupted. In addition to this disadvantage of current techniques, the X-ray radiation itself may be harmful to the patient. Furthermore, another disadvantage of current mammography techniques is that the X-ray radiation can reveal only morphological contrast.
Effective breast cancer screening should be safe and highly accurate in detecting cancers, and should be started from puberty. The procedure should be inexpensive and digital in operation so that comparison between personal results of multiple sequential examinations would be possible. To date, extensive use of such safe breast cancer screening procedures is not a practicality. In
Another technique under development today involves optical mammoscopy with spectroscopy which investigates definite changes produced by cancer in the physiological patterns of tissues, dominantly in the steady state distributions of blood content, oxygenation and metabolic rate. This technique, however, is directed dominantly to achieving as high spatial resolution as in that in morphological imaging. The utilization of lasers to overcome strong multiple scattering of light in the biological tissues makes such a technique rather expensive and questionably safe for screening.
The present assignee has developed a dynamic functional imaging technique of the type described in U.S. Pat. Nos. 5,865,167 and 5,747,789; and more specifically to an optical functional mammoscopy technique as described in U.S. Pat. No. 5,730,133. In such a technique, more specifically denoted as dynamic functional optical marmoscopy (DFOM), near infrared radiation in the wave length range of 0.6-1.1 microns is utilized. This near infrared radiation is very similar to regular background illumination and, therefore, eliminates many of the problems associated with past devices which rely upon lasers. Further, the intensity applied (10-30 mW/cm) is comparable with that of background thermal infrared radiation. Consequently, the utilization of DFOM is absolutely safe. Further, this technique applies the transient functional patterns of tissues with the pixels being temporal signatures of spontaneous tissue functioning and reactivities in response to selected stimuli which are reflective of a whole organ""s synergy. Such an approach is extremely effective for the examination of mammary glands or breasts characterized by high symmetrical physiological functioning and structure, biologically directed to the nipple. In this case, temporal sequences of optical images are recorded. To obtain the specificity of the temporal signatures necessary for pathology transient pattern recognition, the interframe intervals should be differentially small against the time constant of the physiological process
One drawback to such a dynamic functional optical mammoscopy technique is the utilization to date of hard or rigid holders therewith. The same difficulties encountered by the use of such rigid holders in past techniques also constitute a problem when utilized with the dynamic functional optical mammoscopy technique. It is therefore necessary to develop in conjunction with such a dynamic functional optical imaging system a holder which can form an integral part thereof, be reliable in obtaining accurate results and overcome the problems associated with past holders.
It is, therefore, an object of this invention to provide a dynamic functional optical imaging system which can be utilized in conjunction with the study of biological objects and utilizing a non-rigid object holder therewith.
It is another object of this invention to provide a non-rigid holder for use in medical procedures, especially breast examinations.
It is the further object of this invention to provide a dynamic functional optical imaging mammoscopy system which overcomes the problems of past cancer diagnostic and screening techniques.
The objects set forth above as well as further and other objects and advantages of the present invention are achieved by the embodiments of the invention described hereinbelow.
The present invention incorporates a non-rigid biological object holder within a dynamic functional imaging system, and, in particular, a dynamic functional mammoscopy system which is capable of performing accurate breast cancer screening. It should be realized, however, that this holder is not limited to use as only a breast holder and may be used, for example with other parts of the body such as the abdomen, muscles or even an entire body as in the case of an infant or other biological objects. Within the system of this invention, a biological object such as the breast can be placed between one or more flexible, elastic, resilient membranes that form parts of an inflatable bag system. A single flexible, elastic, resilient member (soft holder) is used with the preferred embodiment for the present invention. The examination takes place under controlled external pressure and thereby overcomes many of the problems associated with past hard plate holders as used in mammography or optical mammoscopy systems. The external pressure control together with the optical system of the dynamic functional imaging system operates in a synergistic fashion with the non-rigid holders of the present invention.
The design of the present invention, made up of a number of different embodiments including but not limited to three way adjustability features as well as the removability of the resilient membrane (soft holder), overcomes the problems associated with past breast cancer screening techniques, examples of which are described above, and enables the breast cancer screening technique to take place in a safe, inexpensive and highly accurate manner.